Finned latch bolt assembly



Nov- 22, 1960 c. c. HILLGREN FINNED LATCH BOLT ASSEMBLY Filed July 27, 1959 INVENTOR. 6024 6, 15044625 BY M ASAMAA flrraeA/sys.

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United States Patent FINNED LATCH BOLT ASSEMBLY Carl C. Hillgren, Newport Beach, Calif., assignor to Hillgren Manufacturing Company, Huntington Park, Calif., a corporation of California Filed July 27, 1959, Ser. No. 829,789

1 Claim. (Cl. 292-164) This invention relates to door latches and more particularly to an improved latch bolt assembly for a door latch to be received in a bore formed in the. free edge of a door.

It is an object of this invention to provide a door latch assembly having means for preventing loosening of the assembly in the door which ordinarily occurs inconventional door latch mechanisms after an indefinite number of door closings.

Another object of this invention is to provide a door latch assembly which is adapted to be installed easily and simply, i.e. merely by driving or pressing the same into a bore formed in the door whereby the assembly may be connected to a conventional retractor mechanism actuated by turning of a door knob to withdraw the latch bolt from its projected position in a strike plate of the door frame.

Still another object of this invention is to provide a latch bolt assembly of the above mentioned character having a trim plate which does not require mortising of the door as for conventional latch mechanisms having a face plate secured in a mortise in. the door as with screws.

Further objects and advantages will appear during the course of the following part of'this specification wherein the details of construction and mode of operation of a preferred embodiment of the invention are described with reference to the accompanying drawing, in which:

Fig. l is a side elevation of a door taken in a direction toward the free edge surface of the door, the door having a latch bolt assembly of this invention installed therein;

Fig. 2 is a section on an enlarged scale taken along line 22 in Fig. 1;

Fig. 3 is a cross section taken along line 3-3 in Fig. 2; and

Fig, 4 is a section taken along line 4-4 of Fig. 2, various parts being shown in plan.

Referring to the drawing in detail, there is shown that portion of a door 10, contiguous the free edge surface 11 thereof, in which a door latch is installed, the door latch being designated generally by reference numeral 12 and comprising a latch bolt assembly 13 of this invention. One side surface of the door is designated by reference numeral 15 and the other side surface by numeral 16. The door is adapted to swing on its hinges (not shown) in and out of a door frame having a conventional strike plate mounted therein into which the bolt of the door latch is projected for holding the door in its closed position against a stop surface of the door frame.

Except for the latch bolt assembly 13, the door latch 12 has conventional parts, i.e. two door knobs 18 on the ends of spindles 20 of a retractor mechanism 22, the retractor mechanism being mounted in a cross bore 24 formed in the door and secured therein by rosettes 26, whereby turning of either of the door knobs rotates a spindle for reciprocating the bolt of the latch bolt assembly.

The latch bolt assembly is received in a horizontally extending bore 28 formed to extend from the free edge surface 11 of the door to the cross bore 24. The latch bolt assembly comprises a cylindrical housing 30 having an opening 32 formed in the outer end thereof. A latch bolt 34 is reciprocable axially in the housing and it has a strike surface 35 which is inclined to the direction of reciprocation. When the door is being closed, the inclined surface 35 will engage a strike plate of the door frame to move the bolt inwardly of the housing until the bolt may enter the hole of the strike plate to hold the door closed.

Extending through an end opening formed in-the inner end 37 of the housing is a latch bar 38 which serves to operatively connect the bolt to the retracting mechanism 22 for reciprocating the bolt in the housing. The housing contains conventional springs and lever parts for urging the bolt to its outwardly extended position.

Housing 30 is formed of two elongate parts or halves, one of which is herein referred to as a base half and is designated by numeral 41, and the other being called a cap half and being designated by numeral 42. As best appears in Fig. 3, the base half 41 has a longitudinally extending fiat wall portion 44 and two arcuatewall portions 45 and 46, the longitudinally extending side edges of the arcuate wall portions being designated by numerals 47 and 48, respectively. The cap half 42 likewise has a fiat wall portion. 50 and two arcuate side wall portions 51 and 52., the longitudinally extending side edges of which are designated by numerals 53 and. 54, respectively.- The housing halves are joined together by means of a fastener or rivet 56, with the side edges of the housing halves being in abument whereby the housing defines an inside chamber 58 which receives the bolt and contains the usual spring mechanism for reciprocating the bolt upon actuation of the latch bar 38. Inside chamber 58 is generally oval in cross section having opposed fiat side walls which are defined by the flat portions 44 and 50. The bolt has a cross-sectional configuration corresponding to that of the housing chamber whereby the bolt will slide inwardly and outwardly of the chamber and will not rotate on its longitudinal axis,

Secured to the outer end of the housing base half 41 and preferably made integral therewith is a trim plate 61 which defines the outer end opening 32 of the housing. An edge portion 62 of the trim plate is straight to mate with the fiat side wall 63 of the bolt. The trim plate is large enough in diameter to cover the outer end opening of the horizontal bore 28 and to have the inside edge 65 of the trim plate seated flush upon the surface 11 of the door around the opening of the bore.

The outside surface of the trim plate is beveled as at 66 toward its periphery such that the peripheral edge lies almost flush with the plane of the free edge surface 11 of the door. The trim plate extends inwardly as an annular flange portion 68 of an outside diameter substantially equal to that of the bore 28 so as to fit tightly within the bore. The flange portion has a notch 69 formed therein for receiving a projection 70 on the end of the cap half 42 thus to provide an interconnection between the housing halves for holding them fixed to each other. There is an arcuate projection 72 extending outwardly from the flat wall portion 44 of the base half, the outside surface of the projection being arcuate to conform to the inside wall which defines the horizontal bore 28 thus serving to stabilize the latch bolt assembly in the bore.

The base half 41 of the latch bolt housing has two op positely directed fins 74 and 75 integral therewith and extending longitudinally and radially outwardly from the outside surface of the base half and longitudinally from the inside of the trim plate. These fins are integral along 3 the side edges 47 and 48 of the base half and extend preferably about one-half the length of the housing.

To install the latch bolt assembly in the horizontal bore 28, the inner end portion of the assembly is inserted into the bore and then the assembly is driven or pressed home into the bore until the inside surface of the trim plate seats flush upon the free edge surface 11 of the door. When so driven home, the latch bar will be in position to be engaged by the retracting mechanism. Also, the pressing of the latch bolt assembly into the bore 28 will cause the fins 74 and 75 to cut their own grooves 77 in the side walls which define the bore 28.

It will be found that the fins maintain the latch bolt assembly secure in the door. The assembly will with stand a greatly increased number of door closings and strong slammings without becoming loose. Also, inasmuch as the trim plate is integral with the housing of the latch bolt assembly, it, too, is prevented from becoming loose. Furthermore, by this invention, installation of the latch bolt assembly is made much easier and less time consuming than for conventional door latches in which the trim plate requires mortising of the door and secure ment as with screws.

While I have herein shown and described my invention in what I have conceived to be the most practical and preferred embodiment, it is recognized that departures may be made therefrom within the scope of my invention, which is not to be limited to the details disclosed herein but is to be accorded the full scope of the claim so asto embrace any and all equivalent devices.

Having described my invention, what I claim as new and desire to secure by Letters Patent is:

In the combination of a door and door latch mechanism, the door latch having opposite side surfaces and a free edge surface and a cross-bore extending therethrough and a second bore formed in the door and being open in said edge surface and extending to said cross-bore, said mechanism comprising a latch bolt assembly in said second bore, a reciprocator in said cross-bore and two door knobs connected to the reciprocator for actuating the reciprocator, said assembly comprising a hollow cylindrical housing having an outer end with an outer end opening formed therein and an inner end with an inner end opening formed therein and having an elongate latch bolt reciprocable axially in said housing and through said outer end opening to project outwardly beyond said free edge surface, the outer end portion of said housing being a trim plate which defines said outer end opening and is of greater diameter than said second bore whereby said plate has an inside peripheral edge surface seated flush upon said free edge surface around said second bore, and means operatively connecting said latch bolt to said reciprocator for moving said bolt axially in said housing upon actuation of the reciprocator; the improvement in said housing of the housing being split longitudinally thereof into a base half and a cap half, said base half comprising said trim plate and a semi-cylindrical wall portion extending longitudinally from said plate to said inner end of the housing, said trim plate having a circular flange portion extending inwardly from said inside surface of said plate and being of a diameter to fit snugly in said second bore, said semi-cylindrical wall portion being integral with and extending axially inwardly from said circular flange portion, said base half having two diametrically opposed fins integral with said flange portion and with said semi-cylindrical wall portion and extending longitudinally of and radially outward from the outside surface of said semicylindrical wall portion, said cap half being a semi-cylindrical wall coextensive with said semi-cylindrical wall portion of said base half, said circular flange and said cap half having intermeshing tongue and groove means for interengag ment of said flange and cap half, a fastener for securing said housing halves together, and the door having two grooves formed therein extending longitudinally of said second bore from said free edge surface and being diametrically opposed and complementary in configuration with said fins, with said fins being extended into said grooves respectively, for securing the latch bolt assembly in the door.

References Cited in the file of this patent UNITED STATES PATENTS Beil June 11, 1957 

